Spa



FIG. 1 is a top and front perspective view of the spa of the invention;

FIG. 2 is a top and left side perspective view of the spa illustrated in FIG. 1;

FIG. 3 is a top plan view of the spa illustrated in FIG. 1;

FIG. 4 is a front elevation view of the front of the spa illustrated in FIG. 1, the rear elevation view being identical; and,

FIG. 5 is a left side elevation view of the spa illustrated in FIG. 1, the right side elevation view being identical.

The broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a spa, as shown and described. 